Off highway dump trucks are designed to receive and carry meterial within a bed or dump body of the truck. The bed can be raised by a hydraulic system so as to eject the material from the bed at the appropriate time. Thereafter, the bed can be lowered so that additional material may be loaded within the truck bed.
During cold weather conditions, the material within the truck bed has a tendency to adhere to the walls of the bed, thereby resisting ejection of the material from the bed as it is raised during a dumping or spreading operation. To overcome this problem, it is known in the art to provide a duct system within the walls of the bed so that the flow of exhaust from the truck's engine may be directed into the duct system to heat the bed walls and reduce the tendency of material to adhere to the bed. When the dump bed is raised, the flow of exhaust is redirected or channeled through a separate exhaust diverter and muffler to reduce engine exhaust noise during the dumping operation when the exhaust system is disconnected from the duct system. Over the operating life of the dump truck, this exhaust diverter and muffler will eventually wear out and have to be replaced. Thus, there is a need for an engine noise reduction apparatus and method that eliminates the requirement for an exhaust diverter and muffler associated with a dump truck having a heated bed.
The present invention is directed to overcoming one or more of the problems as set forth above.